Control device



Dec. 19, 1939.

w. s. LANDON CONTROL DEVICE Filed sept. 11.4 1936 2 Sheets-Sheet 1 Dec. i9, 1939. 2,183,854

W. S. LANDON CONTROL DEVICE Filed sept. 11, 195e 2 sheets-Sheet 2 /NVENTOR M A TTORNEY Patented Dec. 19, 193g UNITED STATES CONTROL DEVICE Walter S. Landon,v Detroit, Mich., assignor to Detroit Lubricator Company, Detroit, Mich., a corporation of Michigan Application September 1l, 1936, Serial No. 100,29;`

1o claims. (c1. zas-4s) My 'invention relates' generally tol control devices and more particularly to control devices for controlling flow of iluid.

- One of the objects of my invention is to provide A:i a new and improved actuating mechanism for control devices.

Another object of my invention is to provide in a control device having a valve for controlling ow of fluid, new and improved stop means for limiting movement of the valve.

Another object of my invention is to provide a control device having a new and improved arrangement of thel operating parts thereof.

' The invention consists in the improved construction and combination of parts, to be more fully described hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

In the accompanying drawings, to be taken as 2o a part of this specication, I have fully and clearly illustrated my invention, in which drawings-- Figure l is a top plan-view of a control device,

with the cover removed, embodying features ofA :ny-invention; A

. Fig.' 2 is a view shown in vertical cross section of the device of Fig. l and taken along the line 2 2 of Fig. l:

Fig. 3 is a detailed view of a portion of a valve employed in my device; l

Fig. 4 is a detail view shownin cross section and taken along the line #-4 of Fig. 2:

Fig. 5 is a view shown in vertical central longitudinal cross section of the control device of Fig. 1 and taken along the line l-S of Fig. l;

Fig. 6 is a fragmentary view shown partly in.

elevation and partly incross section of structural details of my device and taken along the line C-l of Fig. 1, and

'Flg. 7 is a fragmentary view shown partly in elevation and partly in cross section of structural detalls of my device and taken along the line 'I-'I of Fig. L.

The control device shown in the drawings, for

the purpose of illustrating my invention, is of the gravity feed type, adapted among other uses to control now of oil by gravity to an oil burner (not shown) and this control device includes a casing, designated in general by the numeral I.

The casing I is preferablya hollow rectangular shaped casing having a bottom wall 2, side walls 3 and end walls 4, these walls cooperating to provide a reservoir chamber 5 for liquid. In the present instance, the casing I is a casting and has an inlet onarnber s beneath the bottom wan 2,

the inlet chamber 6 preferably being in the form of a bore. 'I'he bore or chamber 6 preferably extends longitudinally of and substantially coextensive with the casing bottom wall 2 and has an open end that opens externally of the casing at 5 one end thereof. Adjacent the open end of the chamber 8 there is provided an inlet passage thereto that may be defined by a downwardly projecting hollow boss I to which may be connected one end of a liquid supply line or conduit I. l0 Preferably a strainer I0, Fig. 2, is disposed within the inlet chamber 6 for straining the liquid passing therethrough and the strainer may be tubular in shape and have a fitting provided with an external flange 4II for abutment with the casing l5 outer .wall surface surrounding the open end of chamber l. -Preferably the flange II is clamped tightly against the casing outer wall surface by a suitable clamping means which may include a lever I2. 'I'he lever I2 may be pivoted at one ,2.0

end to the casing I and be positioned to extend across and, intermediate its ends, engage the outer face of the flange II. At its other end the lever I 2 may be provided with an aperture for receiving a screw I3 that may screw-thread luto 25 the casing end wall to hold the flange Il tightly against its seat to seal the opening into chamber 8 in a duid-tight manner. A gasket or washer fil* may be provided between the ilange II and the outer wall surface surrounding the open end a0 of chamber 0 to insure a huid-tight connection.

Adjacent the other endof the chamber I, the

"casing bottom wou 2 is provided with a passage or bore I3! therethrough for the passage of liquid from the inlet chamber 6 into the reservoir cham- A86 ber 5. Preferably the bore I l! extends through an upwardly directed, slightly extended wall portion Il integral with the casing bottom wall 2,

and opens through the upper end of portion I4 into the reservoir chamber 5. Preferably the bore 40 I3n is threadedforreeeiving anexternallythreaded end portion of a tubular shaped, detachable ntting or valve seat member II that projects vertically upward into the reservoir chamber 5.

Mounted on'the upper end of the extended por- 45 tion Il there is a supporting member I6, preferably a U-shaped member having a base portion I'I and upwardly directed, spaced, substantially parallel side members or arms I8. 'I'he base II is preferably apertured substantially midway be- 50 tween the side members l I8 to receive the tubular seat member I5 which serves to rigidly secure the U-shapedsupporting member to the casing. The valve seat member Il may be formed having an external, downwardly facing annular shoulder 66 I8 for bearing against the base I1, and on opposite sides of the base I1, gaskets 28 are preferably provided to insure a leak-proof connection.

Intermediate its ends the; valve seat member I5 has an internal transverse wall 2| having a bore 22 therethrough providing a valve port and an upwardly facing seat 23 for cooperation with the conical face 24 of a reciprocal valve member 25. An upper end portion of the valve member 25 projects upwardly above the upper end of the valve seat member I5, and fitted over and secured to the upper end of the valve seat member there is a cap-like guide member 21 having an aperture for slidably receiving and guiding the reciprocal valve member. In the side wall of the valve seat member I5 and above .the seat 23 there may be provided one or more apertures 28 for the passage of liquid from the valve chamber into the reservoir chamber 5. Pivotally supported on the U-shaped supporting member I6 there is a lever member 38 that is preferably formed having downturned side flanges 3| provided with aligned apertures for receiving a pivot pin 32 that may have its opposite ends secured in and to the side members I8 of the U-shaped support I5. The

lever member 30 has a relatively short lever arm 33 that extends toward the valve member 25 and the end of this lever arm is preferably bifurcated or forked so as to straddle the valve member. 'I'he valve member 25 is preferably formed having a pair of spaced, external annular anges 34 between which end portions of the bifurcated lever arm 33 position for engaging the flanges to actuate the valve. Rigi'dly secured to the other end of the lever 38 there is a oat 35 that actuates the valve member 25 in accordance with changes in the level of the liquid in chamber 5 to maintain the level at a predetermined substantially constant level.

Within the reservoir chamber 5 and preferably integral with the casing bottom wall 2 and with one of the casing side walls 3, there is a wall means 31 that Aextends upwardly from the bottom wall 2 and terminates below the top of the casing I, the wall means 31 preferably projecting inwardly from the side wall 3 intermediate the casing end walls 4. The wall 31 is provided with a vertically extending passage, preferably a bore 38 that opens through the upper face of wall 31 and constitutes a valve chamber in which a valve member 33 is disposed for reciprocal movement to control flow of liquid by gravity from chamber 5. In the side wall of the wall means 31 there may be provided a vertically extending, slot-like opening 48 to communicatively connect the reservoir chamber 5 and the valve chamber 38. The bore 38 opens into a bore 4l of relatively small diameter that is provided in a transverse internal wall 42, adjacent the casing bottom wall 2. The bores 38 and 4I are preferably axially aligned and at their intersection provide a valve port and an upwardly facing seat 43 for the valvemember 33 which preferably has a downwardly facing conical face 44 for engaging the seat 43. The bore 4i preferably has a portion 45 of reduced diameter that opens through the underside of transverse wall 42 and slidably receives a lower end reduced .portion 48 of the valve member for guiding the same. The reduced lower end portion 48 of the valve member 88 projects into a bore 41 that opens through the lower end of an extended portion 48, integral with and depending from the casing bottom wall 2, the bore 41 being closed by a threaded closure plug 48. An outlet opening, preferably in the form of a bore 58, is provided and extends upwardly substantiallyparallel with and'adjacent to the valve chamber 38 between the valve chamber and the casing side wall 3. The outlet bore 5II opens through the underside of the extended portion 48 and may be internally threaded for receiving an externally threaded end of a fuel supply line or conduit 5I, the other end of which conduit may be connected to an oil burner (not shown). A transversely extending bore 52 connects the bore 41 and the outlet bore or passage 50. The bore 58 opens through the top of wall 31 into the reservoir chamber 5 at a point above the liquid level therein, and through the bore .58 gases are vented from the oil supply line to atmosphere.

The reduced portion 46 of the valve member 39 is preferably provided with a V-shaped opening or metering slot 54 in its side wall for the e passage of liquid from chamber or bore 38 into passage 41 when the valve is unseated. The V shaped metering slot 54 preferably converges upwardly from the lower end of the valve member to an apex adjacent the conical face 44 of the valve member. Oil or other liquid enters chamber 38 through opening 40 and when the valve is raised from its seat, as shown, the oil or other liquid ows into bore 4I through the upper portion of the V-shaped slot that is within bore 4I, and from the V-shaped slot into bore -41 whence it passes through bores 52 and 50 into the supply conduit 5I. It will be seen that when the valve is raised further from its seat so that more of the V-shaped metering slot is within bore 4I, a larger quantity of liquid will be permitted to flow from the reservoir 5 to the supply conduit 5I.

The top of the casing I is preferably open, and mounted thereon and closing the casing I there is a second and removable casing 55 that is preferably open at its top and bottom, the top of the casing 55 preferably being closed by a removable closure member or cover 56. The valve member 39 is of rod-like form and projects upwardly into the upper casing 55 and preferably the valve member has an upper rod portion 51 of reduced diameter that slidably engages and is guided in an aperture provided in an inwardly projecting boss or wall means 58 that may be integral with a side wall of the casing 55. The valve portion 51 of reduced diameter provides an upwardly facing annular shoulder 59 and the reduced portion 51 is formed having an annular flange 60 spaced from and above the shoulder 59, the shoulder 58 and ange 88 providing opposed, substantially horizontal abutment surfaces for a purpose to be hereinafter described.

Carried by the casing 55 and removable therewith as a unitary structure is my actuating mechanism for actuating the valve 38, and this actuating mechanism includes a thermostatic power element, designated in general by the numeral 8 I. The power element BI includes a cap-like casing 62 that has an open flanged side that is disposed toward and seats against the outer surface oi' an end wall of the casing 55. The casing 62 may be rigidly secured to the casing 55 by screws 53, or by other suitable means. Within the power element casing 52 there is a metallic bellows 84 that ha's one end hermetically secured and sealed to a fixed wall or plate 65 that is disposed within the casing i2 and positioned at against the inner surface of the end wall thereof. The other, or movable end of the bellows 34 projects into the casing 55 through an aperture in the end wall of the casing, and preferably the'free end of the bellows is hermetically secured and sealed to a movable wall or plate 66. Secured in and to the end wall of the power element casing 62 there is a connecting member or fitting 61 that extends through an aperture in the plate`65 and projects into the bellows, the connecting member 61 having.

a passage or bore 68 that opens through the inner end of the connecting member into the bellows 64. In the present instance, the bore 68 intersects another bore 69 that opens externally of the casing 62 through the side wall of the connecting member 61 and in the bore 68 is secured one end of a tube or conduit 69, the other end of the conduit being connected to a temperature responsive bulb element 16, Fig. l. The power element 6| may be charged with any suitable temperature responsive, expansible-contractible iiuid such as methyl chloride, and the bulb 10 is to be arranged in heat transfer relation with a heating apparatus (not shown) the operation of which is to be controlled. Surrounding the tube 69* at the end that is connected to the connecting member 61 there may be provided a coil or wire 1| and reenforces the tube against breakage at the point of its connection to the connecting member 61.

The side walls of the casing are preferably formed having oppositely disposed, inwardly directed bosses 12, see Fig. 2, and these bosses are preferably provided with aligned .threaded apertures 13 therethrough and through the casing side walls for receiving adjustable supporting members or pivot pins 14. 'I'he pivot pins 14 thread into the apertures 13 from the exterior oi' the casing 55, and inner end portions of the pins project past the inner end faces of the bosses 12 into the casing. Preferably lock screws 16 are employed and threaded into the apertures 13 in engagement with the outer ends of the pins 14 to prevent movement of the ypins from their adjusted or desired positions. may be closed at their outer .ends by disc-like closure members 11 that may be sprung 'into place in the apertures. Each of the pins 14 is provided with a recess in its` outer end and the locking screws 16 are provided with pointed or conical ends to seat one in each recess. When the pins in their desired positions the locking screws 16 are then tightened down, and the pointed ends of the locking screws engaging in the recesses of the pins 14 cause the pins to expand so that the threads of lthe pins 14 will engage tightly with the walls of apertures 13 to prevent movement of the pins.

Disposed within the casing 55 and pivotally supported on the pins 14 there is a. lever member ber 18 is formed having oppositely directed extended edge portions or arms 19, 86 that extend toward opposite side walls of casing 55, and the arm 19 is formed at its outer end having an ear 8| provided with an aperture therethrough to pivotally receive one of the pivot pins 14. The other arm, or arm 86, has an extension member or lever arm 82 that extends longitudinally of the casing toward the outer valv`e stantially parallel with ear 8|, and this lever arm 82 is provided with an aperture therethrough for pivotally receiving the other of the pivot pins 14. An end portion of lever arm 82 positions between the opposed faces ,of the shoulder 59 and the `derstood, however, that the stop that serves to protect the tube from injury The apertures 13- 39 and subange 60 ofy the valve 38 and engages said opposed faces to actuate the valve.

The movable end wall 66 of the bellows 64 is preferably cup-shaped having a central tubular portion 84 that projects into the bellows, and secured in and to theend wall of the tubular pox'- tion 84 is one section 85 of a sectionally constructed connecting rod for connecting the bel-r lows 64 and lever 18. Disposed within the bellows 64 and rigidly Isecured to V'the inner end of the connecting member 61 there is a cap-like stop member 86 that overlies and encloses theA open end of the bore 68 and this stop member 66 is arranged to cooperate with the connecting rod section to limit expansive movement and prevent rupture of the bellows. It is to be unmember 86 only functions as such when the power element as a unit is separate or removed from the control device. The cap-like stop member 86 has an inwardly disposed end wall provided with an aper-v ture therethrough for receiving a reduced end portion 81 of the rod 85, the reduced portion having an enlarged portion' or head 88 that is disposed for longitudinal movement within the cap-like stop member 86 and is adapted to engage the end wall thereof to limit expansive movement ofthe bellows 64. Surrounding the stop member 86 there is preferably provided a helical coil spring 96 that acts to expand the bellows 64, and this spring may have one end in abutment with the fixed wall 65 and the other end in abutment with the bellows movable end wall 66.

'I'he expansible-contractible uid for thepower element is preferably introduced thereinto through a bore or passage 9| provided in the connecting rod section longitudinally therethrough. A filler tube 92 may be screw-threaded and sealed in the outer end of bore 9| and after the power element has been charged the iller tube may be severed and the severed end sealed by solder, or by other suitable sealing material. The end of the rod 85 that projects into the casing 55 preferably has an externally threaded reduced portion, and screw-threaded thereon is a second section 93 of the sectional connecting rod. The rod section 93 has a longitudinally extending bored recess 94 that is internally threaded for receiving the reduced end portion of rod section 85, and the end ofthe ller tube 92- projects into said bored recess and is enclosed by the rod section 93. The lever member 18 is formed, in the present instance, having an embossed or offset portion 95 that extends away from the'bellows movable wall 66 and may be circular in shape, as shown. The offset portion 95 has an aperture 96 therethrough for receiving the rod section 93, the

. rod 93 projecting through said aperture at a point above the fulcrum of the lever 18, as seen in Fig. 2. The aperture 96 is preferably a vertically extending slot and the side edges defining the slot are spaced from the outer periphery of the rod 93. The side edges defining the slot 96 are provided wlth oppositely disposed, inwardly directed, aligned extended portions or bearing members 91, inner end portions' of which engage in an annular slot or recess 98 in the rod 98, see Fig. 4. Opposite sides of the bearing members 91 are preferably rounded or-have convex surfaces, as at 99, for engaging the opposed wall surfaces defining slot 98, the convex surfaces 99 reducing friction between the lineally movable connecting rod and the pivotal lever 18.

An inner end portion |08 of the rod section 93 is preferably of reduced diameter providing an inwardly facing annular shoulder or seating surface I0| and a removable plate-like abutment member |02, apertured tov receive the reduced portion |00, seats against the shoulder |0|. A helical coil spring |03 surrounds the reduced end portion |00 and has one end abutting the abutment member |02 and its other end abutting a similar but movably adjustable abutment member |05. The spring |03 is held under compression between the abutment members |02 and |05 and exerts a force opposing the power element and acting to pivot lever 'I3 in a counterolockwise direction, as seen in Fig. 5.

The adjustment means for regulating the force exerted by the spring |03 is carried by the casing 55 and supported by the vertical wall thereof, opposite the power element, this wall being designated by the numeral |06. 'I'he wall |06 is preferably formed having an inwardly projecting boss |01 provided with a bore |03 therethrough, the longitudinal axis of bore |03 being substantially in alignment with the axis of the bellows 64 and the spring |03. Preferably the bore |08 has an outer end threaded portion |00 of reduced diameter that opens through the casing wall 106, and adjustably screw threaded into bore |03 is the spring( adjusting means which preferably includes a tubular member ||0 having an external threaded portion intermediate its ends for screw threading into bore |09. An outer end portion of the tubular member 0 projects externally of the casing 55 and secured to said outer end portion there is preferably a knob ||2 or other suitable means for conveniently rotating the member I l0.

The spring adjustment means includes a thrust rod ||3 that is carried by and is adjustably screw threaded into the tubular member ||0. An outer end portion ||5 of the thrust rod ||3 ls preferably of enlarged diameter and externally threaded for screw threading into the tubular member ||0, the tubular member preferably having a reduced bore portion at its inner end for slidably receiving and guiding the thrust rod II3. Preferablya locking screw, as at H6, is screw threaded into the outer end of the tubular member I|0 and has a pointed end that positions in a recess in the outer end of thrust rod H3. After the thrust rod ||3 has been adjusted to its desired position the locking screw IIS is tightened and the pointed end thereof engaging in the recess of the' rod I I3 expands the rod circumferentially so that the outer periphery of the rod tightly engages the wall of the threaded aperture to thereby prevent 'loosening of the rod. The thrust rod I3 projects beyond or extends past the inner end of the tubular member ||0 and the movable adjustment member |05 is provided with a central aperture therethrough ior receiving a reduced end portion of the rod ||3, the reduced portion ||'I providing an inwardly facing annular shoulder for seating against abutment member |05. The reduced portion ||1 extends centrally through the coil spring |03 into a bored recess |20 provided in the connecting rod section 33 longitudinally thereof, and the thrust rod`serves to limit lateral movement of the connecting ro and associated parts.

Integral with the end wall |06 of casing 55 there is a pair of horizontally spaced lugs or bosses'l22 that project into the casing toward the opposite end wall thereof, and these bosses are preferably located adjacent the upper end of the casing and positioned one adjacent each of the opposite side walls thereof. A pair of plate-like lever members |23 and |2d are pivotallyfsupported, one on each of the lugs |22, and extend therefrom substantially'parallel with each other toward the opposite end wall of the I casing 55. 'I'he lever members |23, |20 may be formed at their pivoted ends having spaced, substantially horizontal and parallel ears |'between which the lugs |22 position, and the ears and lugs may be provided with aligning apertures to receive vertically disposed pivot pins |28 for pivotally connecting the levers to the supporting lugs |22. The levers |23, |24 are thus supported for pivotal movement in planes substantially transverse to the plane of movement of lever 18 about its fulcrum. The lever 'I3 is formed having an upwardly directed arm |21 that is preferably formed at its upper end having an ear or flange portion |23 that is disposed substantially midway between and extends substantially parallel with levers |23, |24, toward end wall |06. The ange portion |28 is provided with an aperture therethrough in which a bearing member |30 is positioned and rigidly secured to the ilange portion, and this bearing member is provided with sockets or conical recesses |3| in its opposite faces or ends. The free ends of the levers |23, |24 position on opposite sides of the arm flange portion |28 and are provided 'with inwardly facing sockets or conlcal recesses |33. The levers |23, |24 are connected to lever 'I8 by thrust members |34, preferably rods or pins, which terminate at their opposite ends in conical points seating in the pairs of sockets |3| and |33. 'Ihe pins |34 are held in the sockets in engagement with levers |23, |24 by a tension spring |36 secured at its oDDOsite ends to the levers |23, |24, urging the levers toward each other. The spring |33 is preferably of the helical coil type terminating 'at its ends in hooks |31, one of which cooperates in vholding relation with a U-shaped loop member |38 connected to and carried by the lever arm |23. The other hooked end of the spring |36 positions in an aperture in an adjustment member |39 that is carried by the lever |24 and by means of which adjustment member the tension force of spring |36 may be regulated as desired. The adjustment member |38 may be ln the form of a screw that may be threaded into an internally threaded tubular supporting member |40 secured in and to the lever |24. The sockets |33 of the levers |23, |24 are substantially in alignment with each other, but the sockets |3| of the lever 'I3 are preferably slightly out of alignment with the sockets |33 when the valve 39 is in open position so that the pins |34 are slightly angularly disposed with their inner ends positioned closer to the powerl element than their outer ends, as shown in Fig. 1. The coil spring |33 exerts a force acting through levers |23, |24 and pins |34 tending to pivot lever 18 in a counterclockwise direction, as seen in Fig. 5. When the combined forces exerted by the springs |38 and |03 are overcome by the' power element, the valve 39 will be actuated with a snap action by the power element.- The temperature at which the power element will overcome the springs |36 and |03 may be determined, or selected, by adjusting the force ex-A erted by the spring |03, -and preferably indicating means such as a pointer |4| is 'lovided and actuated by the spring adjustment means for indicating and aiding in setting the device to operate at a desired temperature.

A t its inner end the hollow boss |01 is formed aieae'si having an extended, substantially horizontal, externa! wall portion |42 that is integral with and projects laterally from the side wall of the boss, and this wall |42 has a vertically extending bore therethrough for receiving a shaft |43 thatis journaled for rotation in the bore. A lower end portion oi' the shaft |43 preferably projects below the underside of wall |42 and a pinion gear Meis secured to the lower end of the shaft for rotation therewith. The shaft |43 may be formed having a downwardly facing annular shoulder |45 for seating on the upper surface of wall |42, as shown. Formed on an inner end portion of the tubular adjustment member IIB there is a gear rack |46 positioned for 1ongitudinal movement within bore inl, and the side wall dening bore |08 is provided with an opening therethrough, below wall |42, to permit engagement between the rack |46 and gear |44.

The rotatable shaft |43 extends vertically upward from the boss |01 and an upper end portion of the shaft may be of reduced diameter, as at |65, and be positioned i-n an aperture in the cover 56 to steady the shaft. The pointer |4| may be secured to the shaft |43 within casing 55, adjacent the underside of the cover 56, and at its free end the pointer |4| may have an upturned end portion |49 for movement in an arcuate slot |52 provided in the cover 56. On the outer or upper face oi the cover 56 Suitable indicia (not shown) may be provided tor cooperation with the pointer |4| to indicate the setting of the device.

Adjustably screwfthreaded into the wall 58 there is a pair oi spaced. laterally positioned, adjustable stop members |5| and '|52 for limiting movement of the valve 3l. The stop members |5| and |52 project below the underside of the wall 58 and at their lower ends preferably have external annular flanges |53, |54 respectively, for abutment with the annular ilange 69 of the valve 39. The valve 39 extends between and longitudinally of. the stop members |5|, |52 and the stop member |5| is arranged to limit movement of the valve in a valve opening direction, while the stop member |52 limits movement of the valve in a valve closing direction. A plate member |55, preferably formed of spring sheet metal, is apertured to receive the stop members |5|, |52 and is clamped flat against the underside of wall 5l by nuts |55* that thread onto the stop members. The plate member |55 has downturned ilanges |56 that engage with one of the ilattenedsides of the nuts to prevent rotation of the nuts and the flanges and also act to increase friction between the stop members |5I, |52 and the nuts so that the stop members will be held against accidental movement. Resilientor spring means, preferably lock washersas at |58, are provided one between each of the nuts |55* and the plate member |55 to increase the resistance to movement or turnning of the screw threaded stop members so that their adjustment will not be altered accidentally or through vibrations of the device. I have found that by tightening down the nuts |55 as far as they will so, and then turning the nuts back approximately a quarter of a turn it will permit the adjustable stop members to be easily adjusted and yet suillcient resistance to rotation of the stop members will be had to prevent their accidental movement.

The operation of my device is as follows: the temperature of the bulb T0 is at, or below a predetermined temperature, the lever 18 will be in vthe position shown in the drawings and the springs |03 and |35 will hold the valve I! in an open position. Oil will ow from the reservoir Ychamber 5 through the valve port 43, passages 52, 50 and the supply conduit 5| -to an oil burner oi' a heating apparatus. As the temperature of the heating apparatus increases, the fluid in bulb 'IQ expands exerting a force on the bellows 54 tending to expand'the bellows. This force builds up and when it exceeds the force exerted by the springs |03 and |86 in a clockwise direction, as seen in Fig. 5, and the valve 39 will be moved toward closed position, limited by the stop member |54. The stop means |5| and |52 may be adjusted so as to obtain a desired maximum ow capacity when the valve I9 Vis engaging the stop |5|, and a desired minimum flow capacity when the valve is engaging the stop member |52. When the valve 39 is moved to the minimum flow position the temperature of the bulb 10 decreases with corresponding decrease in the force exerted by the power element. When the force exerted by the power element becomes less than the force exerted by the springs |53 'and |36 these springs will pivot the lever 'i8 in a counterclockwise direction, as seen in Fig. 5, moving valve 39 toward open position to increase the quantity of fuel flow to a burner.' A

What I claim and desire to secure by Letters Patent of the United States is: 1. In a control device having a movable controlling means, an actuating mechanism for said controlling means comprising a power element operable positively to move said controlling means in one direction, a lever member movable by and with said power element and operable to trans- .mit directly the torce of said power element to said controlling means, -yieldable 'means acting 0n said lever member and operable to move said controlling means in the opposite. direction, 'a lever member separate from said first-named lever member and fulcrumed to pivot in a pianesubstantially transverse tothe plane of movement of said mst-named lever member, a thrust inem-I ber connecting said lever members, and yieidable means acting on said separate lever member and exerting a. force through said thrust member against said mst-.named lever member tooppose movement or said controlling means by said power element.

device having a movable con- 2. In a control trolling means, a plate-like lever for moving said operable to pivot said lever in one direction, a connecting member for operatively connecting said bellows and said lever and extending through said aperture, said connecting member having a recess therein-onl the other side of said lever, a coil spring surrounding said connecting said other side of said lever :md having one end acting asainst said levensaid coil spring exerting a force operable to pivot said leverl in the opposite direction, a movable abutment member for the other end of said spring and having an aperture therethrough, and manually operable means for moving said abutment meme ber to regulatethe force of saidisprlng and exi tending through said aperture into said recess for guiding said connecting member.

3. In a control device having a controlling means and an actuating means therefor. a plate- 4like lever member for operatively connecting the controlling means and the actuating means, a

the lever 18 will be pivoted supporting means for pivotaily supporting said lever member, said lever member having an aperture therethrough and having a bearing member extending substantially transverse to the plane of movement of said lever member about its iulcrum, and a linearly movable thrust member for connecting the actuating member and said lever member, said thrust member extending through said aperture and having a socket for receiving said bearing member.

4. In a control device having a controlling means and an actuating means therefor, a platelike lever member for operatively connecting the actuating means and the controlling means, a supporting means for pivotally supporting said lever member, said lever member having an aperture therethrough with the wall deiining said aperture having a pair of oppositely disposed in- 'wardly directed extended portions, and a linearly movable thrust member actuated by the actuating means and extending through said aperture, said thrust member having sockets for receiving said extended portions to rock said lever member with said sockets having opposed bearing surfaces, said extended portions having opposed face portions convexly formed for rocking engagement with the'opposed bearing surfaces of said sockets.

5. In a device of the character described, a supporting member, a controlling means, a stop member for said controlling means and adjustably screw-threaded into said supporting member, a nut screw-threaded onto said stop member, resilient means held under tension by said nut to increase the resistance to movement of the stop member, and a plate member held to said supporting member by said nut and having a iiange portion positioned relative to said nut to prevent rotation of said nut.

6. In a control device having a movable controlling means, a lever for moving said controlling means, a power element operable to pivot said lever in one direction, a connecting member for connecting said power element and said lever, a coil spring surrounding said connecting member and having one end acting against said lever, said coil spring exerting a force operable to pivot said lever in the opposite direction, a movable abutment member for the other end of said spring and having an aperture therethrough, and manually operable means for moving said abutment member to regulate the force of said spring and extending through said aperture and guiding said connecting member.

7. A control device comprising a xed supporting means, a lever member having a pair of substantlally parallel arms pivotally connected to said supporting means and having a third arm positioned between said parallel arms, actuating means operable to pivot said lever member, a movable controlling means operatively connected to and movable by one oi said parallel arms, a pair of lever members pivotally mounted on said nxed supporting means, a thrust member extending from the free end of one oil said pair of lever members and engaging said third arm, a thrust member extending from the free end of the other of said pair of lever members and engaging said third arm, and yieldable means urging said pair of lever members toward each` other and acting through said thrust members to pivot said iirstnamed lever member in one direction and oppose said actuating means.

v 8. A control device comprising a xed supporting means, a lever member having a pair of substantially parallel arms pivotally connected to said supporting means and having a third arm positioned between said parallel arms, actuating means operable to pivot said lever member, a movable controlling means operatively connected to and movable by one of said parallel arms, a pair of lever members pivotally mounted on said fixed supporting means and extending one on either side of said third arm, said pair of lever members being in a substantial horizontal plane intersecting said third arm, a thrust member extending from the free end of one of said pair oi' lever members and engaging said third arm, a thrust member extending from the free end of the other of said pair of lever members and enygaging said third arm, and spring means urging said pair of lever members toward each other `and acting through said thrust members to pivot said first-named lever member in one direction and oppose said actuating means.

9. In a device of the character described, a substantially rectangular casing having oppositely disposed end walls and side walls, one of said end walls having an aperture therethrough, a power element secured to said one end wall external of said casing and having a portion thereof pro- Y jecting through said aperture and within said casing toward the other of said end walls, a helical coil spring longitudinal of said casing and having one end engaging said power element projecting portion, said other end wall having a threaded aperture therethrough, manual adjusting means extending from the exterior o`f said casing and threaded within said threaded aperture and having a portion thereof engaging the other end of said spring and operable to hold said spring under compression against said power element, a lever member positioned laterally of said casing and pivotally supported on said casing side walls and engaged by said power element, and a pair of lever members hinged at one end thereof to' said other end wall and having the extended ends thereof extending substantially longitudinally of said casing, said. lever member having a portion thereof projecting between said pair of lever members, a thrust member connecting one of said pair of lever members and said rstnamecl lever member portion, a second thrust member connecting the other of said pair oi lever members and said first-named lever member portion, a helical coil spring operable to urge said pair of lever members together, and valve means engaged and operated by said iirst-named lever member.

10. In a device of the character described, a substantially rectangular casing having oppositely disposed end walls and side walls, one oi said end walls having an aperture therethrough, a power element secured to said one end wall external of said casing and having a portion thereof projecting through said aperture and within said casing toward the other of said end walls, a helical coil spring longitudinal of said casing and having one end engaging said power element projecting portion, said Other end wall having a threaded aperture therethrough, manual adjusting means extending from the 4exterior of said casing and threaded within said threaded aperture and having a portion thereof engaging the other end of said spring and operable to hold said spring under compression against said power element, a lever member having a pair o! substantially parallel arms pivotally connected to said casing side walls and engaged by said power element, a pair of lever members hinged at one bers und said third arm, a helical coil spring operable to urge said pair oi' lever members together,

and valve means operable for vertical movementY and engaged and operated by one of said pair oi parallel arms.

WALTER s. LANDON.

connecting the other o! said pair of lever memj Y 

